ADADC80-Z-12 Analog Devices Inc, ADADC80-Z-12 Datasheet - Page 12

• Manufacturer Part Number: ADADC80-Z-12
• Description: IC ADC 12BIT INTEGRATED 32-CDIP
• Manufacturer: Analog Devices Inc

Specifications of ADADC80-Z-12

• Data Interface: Parallel
• Number Of Bits: 12
• Sampling Rate (per Second): 40k
• Number Of Converters: 1
• Power Dissipation (max): 800mW
• Voltage Supply Source: Analog and Digital, Dual ±
• Operating Temperature: -25°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 32-CDIP (0.900", 22.86mm)
• Resolution (bits): 12bit
• Input Channel Type: Single Ended
• Supply Current: 70mA
• Digital Ic Case Style: DIP
• No. Of Pins: 32
• Operating Temperature Range: -25°C To +85°C
• Lead Free Status / RoHS Status: Lead free / RoHS non-compliant

ADADC80
Other Ranges
Coding relationships and calibration points for 0 V to +5 V,
−2.5 V to +2.5 V, and −5 V to +5 V ranges can be found by
halving the corresponding code equivalents listed for the 0 V to
+10 V and −10 V to +10 V ranges, respectively.
Zero and full-scale calibration can be accomplished to a
precision of approximately ±1/4 LSB using the static adjustment
procedure described previously. By summing a small sine- or
triangular-wave voltage with the signal applied to the analog
input, the output can be cycled through each of the calibration
codes of interest to more accurately determine the center (or
end points) of each discrete quantization level. A detailed
description of this dynamic calibration technique is presented
in A/D Conversion Notes, D. Sheingold, Analog Devices, Inc.,
1977, Part II, Chapter 3.
GROUNDING
Many data-acquisition components have two or more ground
pins that are not connected together within the device. These
grounds are usually referred to as the logic power return, analog
REFERENCE
OUTPUT
INST. AMP
AD521
0.01
µF
*ANALOG
0.01
GROUND
µF
*IF INDEPENDENT, OTHERWISE RETURN
AMPLIFIER REFERENCE TO MECCA AT
ANALOG P.S. COMMON.
+15V
SAMPLE AND
ANALOG
0.01
Figure 15. Basic Grounding Practice
µF
AD583
HOLD
PS
C
0.01
µF
Rev. E | Page 12 of 16
–15V
COM
DIG
DIGITAL
GROUND
C
15V OR
12V
17
DIGITAL
common (analog power return), and analog signal ground.
These grounds must be tied together at one point, usually at the
system power-supply ground. Ideally, a single solid ground is
desirable. However, because current flows through the ground
wires and etch stripes of the circuit cards, and because these
paths have resistance and inductance, hundreds of millivolts can
be generated between the system ground point and the ground
pin of the ADADC80. Therefore, separate ground returns
should be provided to minimize the current flow in the path
from sensitive points to the system ground point, and the two
device grounds should be tied together. In this way, supply
currents and logic gate return currents are not summed into the
same return path as analog signals, where they would cause
measurement errors.
Each of the ADADC80 supply terminals should be capacitively
decoupled as close to the ADADC80 as possible. A large value
capacitor, such as 1 μF in parallel with a 0.1 μF capacitor, is
usually sufficient. Analog supplies are bypassed to the analog
power return pin, and the logic supply is bypassed to the logic
power return pin.
0.01
PS
µF
ANALOG
GND
15
5V
0.01
ADADC80
µF
–15V OR
–12V
25
DIGITAL
GND
10
0.01
µF
DIGITAL
SUPPLY
5V
9